P2564 [SCOI2009] 生日礼物

P2564 [SCOI2009] 生日礼物

#include <bits/stdc++.h>
using namespace std;

#define int long long
const int maxn = 1e6 + 10;
struct node{
	int pos,cate;
};
vector<node> v;
int n,k,cnt[maxn] = {0},type = 0;
bool cmp(const node &a ,const node &b){
	return a.pos < b.pos; 
}

signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0);
	cin >> n >> k;
	for(int i = 1; i <= k; i++){//种类 
		int t;cin >> t;
		while(t--){
			int p;cin >> p;
			v.push_back({p,i});
		} 
	}
	sort(v.begin(),v.end(),cmp);
	//for(int i = 0; i < n; i++)
	//cout << i <<" " << v[i].cate << " " <<v[i].pos << endl;
	int l = 0, r = 0,ans = 0x3f3f3f3f;
	while(r < n){
		if(!cnt[v[r].cate]) type++;
		cnt[v[r].cate]++;
		
		while(type == k){
			ans = min(ans,v[r].pos - v[l].pos);
			cnt[v[l].cate]--;
			if(!cnt[v[l].cate]) type--;
			l++;
		}
		r++;
	} 
	cout << ans;
	return 0;
}

　

 

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